Consuming media presentations generally involves listening to audio information and/or viewing video information such as, for example, radio programs, music, television programs, movies, still images, etc. Media-centric companies such as, for example, advertising companies, broadcasting networks, etc. are often interested in the viewing and listening interests of their audience to better market their products. A technique often used to measure the number and/or demographics of audience members exposed to media involves awarding media exposure credit to a media presentation each time an audience member is exposed to (e.g., is in the vicinity of) the media presentation.
The media exposure activities of audience members may be monitored using personal portable metering devices (PPMs), which are also known as portable meters, portable metering devices, and/or portable personal meters. A PPM is an electronic device that is typically worn (e.g., clipped to a belt or other apparel) or carried by an audience member. Some PPMs are configured to monitor media exposure by detecting or collecting information (e.g., program or source identifier codes, signatures, etc.) from audio and/or video signals that are emitted or presented by media delivery devices (e.g., televisions, stereos, speakers, computers, etc.).
An audience member or monitored individual performs their usual daily routine while wearing a PPM. The monitored individual's daily routine may include listening to the radio and/or other sources of audio media and/or watching television programs and/or other sources of audio/visual media. As the audience member is exposed to (e.g., views, listens to, is in the vicinity of, etc.) media, a PPM associated with (e.g., assigned to and carried by) that audience member generates monitoring data.
Unfortunately, the typical household presents unique monitoring challenges to the PPM. For example, a typical household includes multiple media delivery devices, each configured to deliver media content to specific viewing and/or listening areas located within the home. A PPM, carried by a person who is located in one of the viewing and/or listening areas, is configured to detect any media content being delivered in the viewing and/or listening area and to credit the programming associated with the media content as having been delivered to the corresponding audience member. Thus, the PPM operates on the premise that any media content detected by the PPM is associated with programming to which the person carrying the PPM was exposed. However, in some cases, a PPM may detect media content that is emitted by a media delivery device that is not located within the viewing or listening proximity of the person carrying the PPM, thereby causing the detected programming to be improperly credited.
The ability of the PPM to detect audio/video content being delivered outside of the viewing and/or listening proximity of the person carrying the PPM is an effect referred to as “spillover” because the media content being delivered outside of the viewing and/or listening proximity of the person carrying the PPM is described as “spilling over” into the area occupied by the person carrying the PPM. Spillover may occur, for example, in a case where a monitored individual in a bedroom is reading a book, but their PPM detects audio/video content delivered by a television in an adjacent living room (i.e., outside of their viewing/listening proximity), thereby causing the person carrying the PPM to be improperly credited as a member of the audience for the audio/video content.
Another effect, referred to as “hijacking” occurs when a person's PPM detects audio/video content being emitted from multiple media delivery devices at the same time. For example, an adult watching a television news program in a household kitchen may be located near a household family room in which children are watching a television cartoon program on a different television. Yet, the cartoon programming delivered by the family room television may, in some cases, have signals that overpower or “hijack” the signals associated with the news programming being emitted by the kitchen television. As a result, information collected by the adult's PPM may lead to inaccurately crediting the cartoon program as having been viewed by the adult and failing to credit the news program with any viewing. Still further, other common difficulties such as varying volume levels, varying audio/video content type (e.g., sparse, medium, rich, etc.), varying household transmission characteristics due to open/closed doors, movement and/or placement of furniture, acoustic characteristics of room layouts, wall construction, floor coverings, ceiling heights, etc. may lead to inaccurate audio/video content exposure detection by PPMs.